Tributyrin administration improves intestinal development and health in pre-weaned dairy calves fed milk replacer.

Butyrate and its derivatives possess various nutritional and biological benefits for mammals, whereas its effects on dairy calves have not been well characterized. This study evaluated the effects of tributyrin administration on blood immune, intestinal immune and barrier functions, and microbial composition of pre-weaned dairy calves. Twenty newborn Holstein bull calves were randomly assigned into a control group (no tributyrin supplementation, CON; n = 10) or a treatment group (supplemented with tributyrin at 2 g/L of milk, TRB; n = 10). The results showed that diarrhea frequency was decreased significantly by tributyrin administration from d 29 to 56 (P < 0.001) and the whole period (P = 0.003, d 1 to 56) though no significant effects were observed on growth performance. For blood metabolites, tributyrin administration significantly reduced the concentration of interleukin-1ß (IL-1ß) on d 28 (P = 0.001) and tended to reduce the concentration of serum amyloid A on d 56 (P = 0.079), whereas serum oxidative status parameters were not affected. For intestinal development, tributyrin administration increased the villus height (P < 0.001) and the ratio of villus height to crypt depth (P = 0.046) in the jejunum, and the villus height in the ileum (P = 0.074). Furthermore, toll-like receptor 2 (TRL2, P = 0.045) and IL-1ß (P = 0.088) gene expressions were downregulated, while claudin-4 (P = 0.022) gene expression was upregulated in the jejunum following tributyrin administration. In the ileum, claudin-4 (P = 0.029) and G-protein coupled receptor 41 (P = 0.019) gene expressions were upregulated in the TRB group compared to CON. No significantly higher abundances of microbiota were found in the jejunum or ileum of calves in the CON group. In the TRB group, supplementing tributyrin significantly increased the abundance of short-chain fatty acid (SCFA)-producing bacteria, including Ruminococcaceae, Lachnospiraceae, Prevotella and Rikenellaceae (LDA >3.5, P < 0.05), which was negatively associated with inflammatory gene expression (TLR2 and IL-1ß) but positively associated with intestinal barrier genes (claudin-4) and morphological parameters (P < 0.05). In conclusion, supplementing tributyrin in milk replacer could improve intestinal development and health of pre-weaned dairy calves by stimulating SCFA-producing bacteria colonization, enhancing intestinal barrier functions and suppressing inflammatory responses.

Feasibility of Supplying Ruminally Protected Lysine and Methionine to Periparturient Dairy Cows on the Efficiency of Subsequent Lactation.

The objective of this study was to evaluate the effects of supplying ruminally protected Lys (RPL) and ruminally protected Met (RPM) to transition cows' diets on the efficiency of subsequent lactation. A total of 120 prepartum Holstein cows were assigned into four treatments blocked by the anticipated calving date, previous lactation milk yield, number of lactations, and body condition score and fed either RPL, RPM, or the combination (RPML) or control diet (CON) throughout the transition period (3 weeks before till 3 weeks after calving). From 22 to 150 days in milk (DIM), all animals (100 cows) were fed a combination of RPM and RPL (0.17% RPM and 0.41% RPL of DM; n = 25 cows/treatment) as follows; CON-RPML, RPM-RPML, RPL-RPML, and RPML-RPML. Milk production and dry matter intake (DMI) were measured daily; milk and blood samples were taken at 21, 30, 60, 90, 120, and 150 DIM. Supplemented amino acids (AA) were mixed with the premix and added to the total mixed ration during the experiment. DMI (p < 0.001) and energy-corrected milk (ECM, p = 0.04) were higher for cows that were fed RPML-RPML than other cows. Compared with CON-RPML, yields of milk total protein, lactose, and nitrogen efficiency were increased (p < 0.01), whereas milk urea nitrogen (MUN; p = 0.002) was decreased for other treatments. However, supplemental AA did not affect milk lactose percentage, fat yield, feed efficiency, or serum total protein concentration (p > 0.10). Transition cows that consumed AA had a greater peak of milk yield (p < 0.01), as well as quickly reached the peak of milk (p < 0.004). There were differences in ß-hydroxybutyrate concentration during the early lactation, with a lower level for AA groups (p < 0.05), and the difference faded with the progression of lactation (p > 0.10). Fertility efficiency as measured by pregnancy rate was improved by supplemental AA during the perinatal period (p < 0.05). In conclusion, transition cows consumed RPM and RPL, increased post-calving DMI, milk production, milk protein yield, nitrogen efficiency, and improved fertility performance.

Maternal Supply of Ruminally-Protected Lysine and Methionine During Close-Up Period Enhances Immunity and Growth Rate of Neonatal Calves.

The objective of this study was to evaluate the effect of supplying ruminally-protected lysine (RPL), methionine (RPM), or the two in combination (RPML) to transition dairy cows on the immunity and performance of their offspring. Eighty heifer calves (n = 20 calves per group) were assigned to four treatments based on their dam diet; basal diet (CON), a basal diet with lysine [RPL, 0.33% of dry matter (DM)], a basal diet with methionine (RPM, 0.16% DM), or with the combination (RPML). Calves were fed colostrum from their dams within 2 h of birth. Calves were then fed milk only (d 2-22), a combination of milk and milk replacer (d 23-25), and milk replacer (d 25-60). Starter feed was fed to the calves twice daily after liquid feeding. Calves blood samples were collected after calving on 0, 12, 24, and 48 h and 5 and 7 d after birth. Data were analyzed by SAS software v9.4. Providing ruminally-protected amino acids (RPAA) to transition cows improved colostrum quality compared to the CON (Brix; P < 0.01). Serum total protein concentrations were higher in calves from supplemented cows than in calves from unsupplemented cows (P < 0.01). Calves born to dams in the RPM, RPL, and RPML groups had higher plasma immunoglobulin G (IgG) concentrations 0, 12, 24, and 48 h and 7 d after birth than those born to dams in the CON group (P < 0.05). The percentage of calves with adequate passive immunity transfer was increased with RPM and RPL or the two in combination (P < 0.01). However, there was no difference in the percentage of calves with adequate passive immunity transfer between the RPM and RPL groups (P = 0.21). Calves from cows that receive supplemental RPAA have a greater average daily gain (ADG) than those born to cows in the CON group (P < 0.01). These results indicate that maternal supplementation with RPM or RPL or the two in combination during the periparturient period could be an alternative strategy to improve the performance of calves, especially in accelerated growth programs in calves.

Milk selenium content and speciation in response to supranutritional selenium yeast supplementation in cows.

The effects of selenium (Se) yeast supplementation on performance, blood biochemical and antioxidant parameters, and milk Se content and speciation were evaluated. Thirty-six mid-lactation Holstein dairy cows were randomly assigned to 1 of 3 treatments: 1) control (basal diet containing Se at 0.11 mg/kg DM), 2) basal diet + 0.5 mg supplemental Se/kg DM (SY-0.5), and 3) basal diet + 5 mg supplemental Se/kg DM (SY-5). Selenium was supplemented as Se yeast. The trial consisted of a 1-week pretrial period and an 8-week experimental period. Milk somatic cell score decreased with SY-5 supplementation (P < 0.05), but other performance parameters were not affected (P > 0.05). The serum Se concentration increased with the increasing levels of Se yeast supplementation (P < 0.05), however, blood biochemical parameters showed few treatment effects. The antioxidant capacity of dairy cows was improved with Se yeast supplementation reflected in increased serum glutathione peroxidase activity (P < 0.05) and total antioxidant capacity (P = 0.08), and decreased malondialdehyde concentration (P < 0.05). Milk total Se concentration increased with Se dose (P < 0.05). Also, the selenomethionine concentration increased with Se dose from 13.0 ± 0.7 µg/kg in control to 33.1 ± 2.1 µg/kg in SY-0.5 and 530.4 ± 17.5 µg/kg in SY-5 cows (P < 0.05). Similarly, selenocystine concentration increased from 15.6 ± 0.9 µg/kg in control and 18.9 ± 1.1 µg/kg in SY-0.5 to 22.2 ± 1.5 µg/kg in SY-5 cows (P < 0.05). In conclusion, Se yeast is a good organic Se source to produce Se-enriched cow milk with increased Se species including selenomethionine and selenocystine. The results can provide useful information on milk Se species when a high dose Se yeast was supplemented in the cow diet.

Dietary Bacillus spp. enhanced growth and disease resistance of weaned pigs by modulating intestinal microbiota and systemic immunity.

BACKGROUND: Previous research has shown that dietary supplementation of Bacillus spp. probiotics exerts beneficial effects on animals' growth. However, limited studies have evaluated the efficacy of Bacillus spp. on weaned pigs and their effects on host gut health and microbiome, and systemic immunity using a disease challenge model. The objective of this experiment was to investigate the effects of two Bacillus spp. strains (Bacillus subtilis DSM 32540 and Bacillus pumilus DSM 32539) on growth performance, diarrhea, intestinal health, microbiome, and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli (ETEC). RESULTS: Pigs in PRO1 (Bacillus subtilis DSM 32540) had greater (P < 0.05) body weight on d 7 and 14 PI, greater (P < 0.05) ADG from d 0 to 7 and d 7 to 14 PI, compared with pigs in CON (Control). Pigs in PRO1 had milder (P < 0.05) diarrhea on d 2 and 3 PI compared with pigs in CON. However, no differences were observed in growth performance and diarrhea score between PRO2 (Bacillus pumilus DSM 32539) and CON groups. Supplementation of PRO1 decreased (P < 0.05) lymphocyte counts on d 7 and 14 PI, compared with CON. Supplementation of PRO1 and PRO2 both reduced (P < 0.05) total coliforms in mesenteric lymph nodes on d 21 PI. Pigs in PRO2 had greater (P < 0.05) goblet cell number and sulfomucin percentage in duodenal villi and greater (P < 0.05) sialomucin percentage in jejunal villi than pigs in CON. Supplementation of PRO1 up-regulated (P < 0.05) MUC2 gene expression in jejunal mucosa and reduced (P < 0.05) PTGS-2 and IL1B gene expression in ileal mucosa on d 21 PI, compared with CON. Pigs in PRO1 had reduced (P < 0.05) relative abundance of families Lachnospiraceae, Peptostreptococcaceae and Pasteurellaceae in the ileum. CONCLUSIONS: Supplementation of Bacillus subtilis DSM 32540 improved growth performance, alleviated diarrhea severity, enhanced gut health, and reduced systemic inflammation of weaned pigs infected with ETEC F18. Although Bacillus pumilus DSM 32539 was able to alleviate systemic inflammation, it had limited impacts on growth performance and severity of diarrhea of ETEC F18 challenged weaned pigs.

Comparison of Selenium Source in Preventing Oxidative Stress in Bovine Mammary Epithelial Cells.

Oxidative stress can cause cell damage. Hydroxy-selenomethionine (HMSeBA) is an organic Se source with emerging antioxidant advantages. The objective of this study was to compare the effects of HMSeBA, selenomethionine (SeMet) and sodium selenite (SS) on the antioxidant response and the ability to resist oxidative stress in bovine mammary epithelial cells (BMEC). The BMEC were treated with 0 (Control), 20, 50, 100 and 150 nM HMSeBA, 100 nM SeMet and100 nM SS for 48 h. The results showed that HMSeBA and SeMet treatments had higher glutathione peroxidase (p < 0.01) and catalase (p = 0.01) activities and mRNA abundance of GPX3 (p = 0.02), but lower superoxide dismutase activity compared with SS (p = 0.04). The catalase activity (p < 0.05) and mRNA abundance of GPX3 (p = 0.04) changed in a quadratic manner with the increase of HMSeBA levels. To assess the potential protection of different Se sources against oxidative stress on BMEC, 0 or 50 µM H2O2 was added to BMEC culture for 3 h after Se pre-treatment for 48 h. The results showed that HMSeBA and SeMet, which did not differ (p > 0.05), but further decreased malondialdehyde and reactive oxygen species production compared with SS (p < 0.05). In conclusion, HMSeBA showed an enhanced cellular antioxidant status to resist oxidative damage induced by H2O2 when compared with SS, whereas the effects were similar to SeMet.

Organic selenium supplement partially alleviated diquat-induced oxidative insults and hepatic metabolic stress in nursery pigs.

The study investigated antioxidant effects of Se on resilience to diquat-induced oxidative stress in nursery pigs. Thirty-five weaned pigs were individually housed and randomly assigned to one of the five treatments. Pigs were (1) fed a basal diet and intraperitoneally injected with sterile saline (negative control), (2) fed the basal diet and injected with diquat solution (positive control, PC), or fed the basal diet supplemented with 0·3 mg Se/kg as (3) sodium selenite (SS), (4) soyabean protein-chelated Se (SC) or (5) selenised yeast (SY) and intraperitoneally injected with diquat. Pigs were fed the experimental diets for 17 d and injected with diquat at 10 mg/kg body weight or saline on the 11th day of the study (day 0 post-injection (PI)). Diquat exposure induced acute stress and innate immune activation (P < 0·05) at 6 h PI and compromised (P < 0·05) plasma glutathione peroxidase activity on day 2 PI, which was accompanied by an increase in plasma malondialdehyde at 6 h and day 2 PI (P < 0·10). Organic Se, particularly SY, enhanced (P < 0·05) endogenous antioxidant activity in various aspects compared with the PC group. The growth rate and feed intake from day 0 to day 7 PI were significantly lower in the PC, SS and SC groups than the NC group (P < 0·05). Untargeted metabolomics analysis revealed that twenty-two hepatic metabolites (false discovery rate < 0·15) associated with lipid and cellular antioxidant metabolism were altered by diquat. SY restored hepatic metabolic profiles in some but not all samples.

Effects of Pair Versus Individual Housing on Performance, Health, and Behavior of Dairy Calves.

The aim of this study was to evaluate the effects of pair versus individual housing on performance, health, and behavior of dairy calves. Thirty female Holstein dairy calves were assigned to individual (n = 10) or pair housing (n = 10 pairs). The results showed that both treatments had a similar starter intake and average daily gain (ADG) during the preweaning period. During weaning and postweaning periods, paired calves had a higher starter intake, and the ADG of paired calves continued to increase but calves housed individually experienced a growth check. Paired calves showed higher diarrhea frequency only in week three. The results on behavior showed that feeding, chewing and ruminating time increased, and self-grooming time decreased with age during weaning and postweaning periods, and paired calves spent less time feeding, standing and self-grooming but more time lying during this time. After mixing, feeding, and chewing and ruminating time continued to rise, and self-grooming time continued to decline for both treatments. All calves spent less time standing and non-nutritive manipulation after mixing, and previously individually housed calves tended to increase non-nutritive manipulation. These results showed that pair housing improved growth during weaning and postweaning periods and that calves altered their behavior at different phases. Less social contact may lead to more non-nutritive manipulation.

Chemical Composition and Antioxidant Properties of Essential Oils from Peppermint, Native Spearmint and Scotch Spearmint.

Natural antioxidants have drawn growing interest for use in animal feed and the food industry. In the current study, essential oils (EOs) obtained from hydrodistillation of three mentha species, including Mentha piperita (peppermint), Mentha spicata (native spearmint) and Mentha gracilis (Scotch spearmint), harvested in the Midwest region in the United States, were analyzed for their chemical composition using gas chromatography-mass spectrometry, and their antioxidant properties were assessed through chemical assays, in vitro cell culture modeling and in Caenorhabditis elegans (C. elegans). The activity of ferric iron reduction and free-radical scavenging capacity were assessed through chemical-based assays, including the reducing power assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, and Trolox equivalent antioxidant capacity assay (TEAC). Subsequently, the capacity of EOs to mitigate lipid peroxidation was analyzed at various doses using fresh liver homogenates from pigs. A porcine jejunum epithelial cell line (IPEC-J2) was employed as in vitro model to study the cellular antioxidant activity of the mint EOs. Finally, the effectiveness of mint EOs to alleviate acute systemic oxidative damage were evaluated in vivo using C. elegans. Data were analyzed by the MIXED procedure of SAS. Contrast statement was performed to assess linear or quadratic effects of mint EOs given at various doses. All three EOs are mostly composed of monoterpenes and their derivatives (76-90%), but differed in the major compounds, which are menthol and menthone (50%) in peppermint EO and carvone (70%) in spearmint EOs. Three mint EOs demonstrated prominent radical scavenging and Fe3+ reducing activity in chemical-based assays. In comparison with native and Scotch spearmint EOs, peppermint EO had the lowest (p < 0.05) half maximal effective concentration (EC50) in DPPH and TEAC assays and higher efficacy in the reducing power assay. All three EOs exhibited equivalent activity in mitigation of chemical-induced lipid peroxidation in liver tissues in a dose-dependent manner (linear, p < 0.001). The maximal cellular antioxidant activity (CAA) was observed at 5 µg/mL for peppermint, and 100 µg/mL for native and Scotch spearmint EOs. The addition of 25 µg/mL of both spearmint EOs increased (p < 0.05) cellular concentrations of glutathione in H2O2-treated IPEC-J2 cells, suggesting enhanced endogenous antioxidant defense. Supplementation of 100 µg/mL of peppermint or Scotch spearmint EO significantly increased (p < 0.05) the survival rate of C. elegans in response to H2O2-induced oxidative stress. The protective effect is comparable to that of supplementation of 10 µg/mL of ascorbic acid. However native spearmint EO failed to reduce the death rate within the same supplementation dose (10-200 µg/mL).

Effects of an immunomodulatory feed additive on body weight, production parameters, blood metabolites, and health in multiparous transition Holstein cows.

The study investigated the impact of feeding OmniGen-AF® (OG; Phibro Animal Health, Quincy, IL) from dry-off to week 4 of lactation at two doses on production performance and metabolic adaptation of multiparous Holstein cows. Forty-eight cows were blocked and assigned randomly to three treatments: OG was fed at 0 g/head/day (CON), 60 g/head/day (OG60), or 90 g/head/day (OG90). No difference was observed in dry matter intake (DMI) throughout the experiment, whereas feeding OG tended to decrease the percentage body weight change (PWC) on week 2. Although colostrum yield was not affected by treatment, colostrum IgG production of OG90 tended to be higher than that of CON. OG supplementation did not affect overall milking performance but decreased milk SCC during the first 4 weeks of lactation. In prepartum, OG supplementation decreased the concentrations of serum albumin and calcium, and increased serum globulin. OG supplementation tended to increase serum total protein, globulin, and calcium contents postpartum. Furthermore, reduced incidence of mastitis and udder edema were observed. In conclusion, supplementing cows with OG from dry-off period reduces or modulates the inflammation responses associated with parturition, potentially resulting in improved postpartum health, while feeding OG more than 60 g/head/day did not warrant further benefits.

Effects of Saccharomyces Cerevisiae Fermentation Products on the Microbial Community throughout the Gastrointestinal Tract of Calves.

The effect of Saccharomyces cerevisiae fermentation products (SCFP) on improving growth and health of calves could be attributed to the ability of SCFP to modulate the microbiota in the gastrointestinal tract (GIT). However, the changes in microbial community along the gut in calves supplemented with SCFP have not been investigated extensively. The aims of this study were to investigate the effect of SCFP on microbial communities in each sites of GIT using high-throughput sequencing technique. Fifteen Holstein male calves were used and randomly assigned to 1 of the 3 treatments including a calf starter containing 0 (Control, CON), 0.5 (SCFP1) or 1% SCFP (SCFP2, Original XPC, Diamond V, Cedar Rapids, IA, USA) of dry matter from day 4 to 56. The supplemented calves were fed with an additional 1 g/d SCFP (SmartCare, Diamond V, Cedar Rapids, IA, USA) in milk from day 2 to 30. Rumen fluid was sampled at day 28 of age via esophageal tube. All calves were slaughtered and gastrointestinal samples collected on day 56. Inclusion of SCFP increased the microbial species richness in the large intestine. The SCFP also affected the bacterial community at an early age in the rumen and later in rectum microbiota. Supplementation of SCFP stimulated colonization by fibrolytic bacteria (Lachnospiraceae and Ruminococcaceae) in rumen and large intestine, respectively. No differences were found between SCFP1 and SCFP2. This is the first study to analyze the effect of SCFP on bacterial community of the GIT microbiota in calves. The results provide the basic bacterial community information, which helps us understand the mechanism of action of SCFP for improving the health and performance of pre-weaning calf.

Reduced energy density of close-up diets decrease ruminal pH and increase concentration of volatile fatty acids postpartum in Holstein cows.

The objective of this study was to determine the effect of reduced energy density of close-up diets on ruminal fermentation parameters in transition cows. Fourteen Holstein dry cows were blocked and assigned randomly to three groups fed a high energy density diet (HD, 1.62 Mcal of net energy for lactation (NEL )/kg dry matter (DM)), or a middle energy density diet (MD, 1.47 Mcal NEL /kg DM), or a low energy density diet (LD, 1.30 Mcal NEL /kg DM) prepartum, and were fed the same diet postpartum. The reduced energy density diets decreased the average dry matter intake (DMI) prepartum and tended to increase the DMI postpartum. The ruminal pH of the LD group was significantly higher prepartum and lower during the first week of lactation compared with the other two groups. The reduced energy density diet depressed the average ruminal concentration of propionate and butyrate prepartum, and increased the average concentration of total volatile fatty acids (VFA) postpartum. The LD group had higher populations of Butyrivibrio fibrisolvens and Ruminococcus flavefaciens relative to HD and MD groups on 7 days in milk. In conclusion, the cows fed reduced energy density diet prepartum had higher VFA concentration, but were more susceptible to subacute ruminal acidosis postpartum.

Review: Utilization of yeast of Saccharomyces cerevisiae origin in artificially raised calves.

Yeast of Saccharomyces cerevisiae (SCY) origin has over long time been incorporated into domestic animal diets. In calves, several products have offered improved performance and health. Although several types of research have been completed, the mode of action of SCY is not clear in calves. Under this review, we have highlighted the works available in the literature on the use of SCY in calves performance, health, immunity, and the gut environment. Both active live yeast and yeast culture have positive effects on growth, rumen, small intestines, immunity and general health of the calf. Specifically, SCY can improve DMI, growth, feed efficiency and reduce diarrhea in calves. Furthermore, subtle improvements are seen in rumen fermentation (increased butyrate production) and rumen papillae growth. These positive results are, however, more pronounced in calves that are under stress or exposed to significant levels of disease-causing agents. There is a need for further research in areas such as gut morphology, gut microbiology and immunity using latest molecular methods to fully understand how SCY helps the growth and development of calves.

Effect of reduced energy density of close-up diets on dry matter intake, lactation performance and energy balance in multiparous Holstein cows.

Energy intake prepartum is critically important to health, milk performance, and profitability of dairy cows. The objective of this study was to determine the effect of reduced energy density of close-up diets on dry matter intake (DMI), lactation performance and energy balance (EB) in multiparous Holstein cows which were housed in a free-stall barn and fed for ad libitum intake. Thirty-nine dry cows were blocked and assigned randomly to three groups fed a high energy density diet [HD, n = 13; 6.8 MJ of net energy for lactation (NEL)/kg; 14.0% crude protein (CP) ], or a middle energy density diet (MD, n = 13; 6.2 MJ NEL/kg; 14.0% CP), or a low energy density diet (LD, n = 13; 5.4 MJ NEL/kg; 14.0% CP) from d 21 before expected day of calving. After parturition, all cows were fed the same lactation diet to d 70 in milk (DIM). The DMI and NEL intake prepartum were decreased by the reduced energy density diets (P < 0.05). The LD group consumed 1.3 kg/d (DM) more diet compared with HD group in the last 24 h before calving. The milk yield and the postpartum DMI were increased by the reduced energy density diet prepartum (P < 0.05). The changes in BCS and BW prepartum and postpartum were not affected by prepartum diets. HD group had higher milk fat content and lower lactose content compared with LD group during the first 3 wk of lactation (P < 0.05). The energy consumption for HD, MD and LD groups were 149.8%, 126.2% and 101.1% of their calculated energy requirements prepartum (P < 0.05), and 72.7%, 73.1% and 75.2% during the first 4 wk postpartum, respectively. In conclusion, the low energy density prepartum diet was effective in controlling NEL intake prepartum, and was beneficial in increasing DMI and milk yield, and alleviating negative EB postpartum.

[Preparation of forsythiaside from Forsythia suspensa by high-performance liquid chromato- graphy].

OBJECTIVE: To prepare forsythiaside from Forsythia suspensa by high-performance liquid chromatography (HPLC). METHOD: A crude extract of Forsythia suspensa was prepared by water extraction and alcohol precipitation prior to polyamide column chromatography. Forsythiaside was prepared from the crude extract by RP-HPLC. RESULTS: Analysis with HPLC showed that the purity of the prepared forsythiaside reached 98%. CONCLUSION: HPLC is simple and effective for the preparation of forsythiaside from Forsythia suspensa.